Making Sense of Programmable Logic

O'Reilly Network has reposted an article, called Making
Sense of Programmable Logic, that provides a nice introduction to
programmable logic. It covers the blurring line between hardware and
software and gives an overview that includes CPLDs, FPGAs, VHDL, and
Verilog. Since the article was originally published in 1999, a whole
Open Source hardware design community has evolved that includes the Free Model Foundry, OpenCores.org, and Open Collector, which provides
release announcements for programmable logic and other Open Source Hardware.